Massee and Cooke, with other mycologists, take exception to this
omission and its implication, in their discussion of the subject, giving
consistent reasons for the retention of these groups in systematic
works.

PHYCOMYCETES OR PHYSOMYCETES.

As originally defined by Berkeley, this group was composed chiefly of
the old typical Mucors and their allies, and was then termed
Physomycetes. In the newer system of classification its original
definition has been extended so as to include a number of groups
somewhat dissimilar in their habits and characteristics, but "united
under the conservating bond of a dimorphic reproduction," and the name
has been changed to Phycomycetes. As at present recognized "the
Phycomycetes are characterized by a unicellular mycelium, often
parasitic on plants or animals, sometimes saprophytic, developed in the
air or in water. Reproduction sexual or asexual." As thus interpreted,
Phycomycetes includes the Mucoracei; the Peronosporaceae, or "rotting
moulds;" the Cystopi, or "white rusts;" the Saprolegniaceae, or "fish
moulds;" the Entomophthoraceae, or "insect moulds," together with a few
minor groups of doubtful natural affinity.

BIBLIOGRAPHY.

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